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  • 1.
    Ajalloueian, F.
    et al.
    Isfahan Univ Technol, Dept Text Engn, Ctr Excellence Appl Nanotechnol, Esfahan, Iran..
    Fransson, M.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Tavanai, H.
    Isfahan Univ Technol, Dept Text Engn, Ctr Excellence Appl Nanotechnol, Esfahan, Iran..
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Magnusson, Peetra
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology. Uppsala Univ, Dept Immunol Genet & Pathol IGP, Uppsala, Sweden..
    Arpanaei, A.
    Natl Inst Genet Engn & Biotechnol, Dept Ind & Environm Biotechnol, Tehran, Iran..
    Comparing PLGA and PLGA/Chitosan Nanofibers Seeded by Msc: A Cell-scaffold Interaction Study2015In: Tissue Engineering. Part A, ISSN 1937-3341, E-ISSN 1937-335X, Vol. 21, p. S406-S407Article in journal (Other academic)
  • 2.
    Ajalloueian, F.
    et al.
    Tech Univ Denmark, Copenhagen, Denmark..
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Fossum, M.
    Karolinska Inst, Stockholm, Sweden..
    Chronakis, I. S.
    Tech Univ Denmark, Copenhagen, Denmark..
    Integrated Micro/Nanofibrous PLGA-Collagen Scaffold: an Optimized Method for Plastic Compression of Collagen into PLGA Microfibers2015In: Tissue Engineering. Part A, ISSN 1937-3341, E-ISSN 1937-335X, Vol. 21, p. S347-S347Article in journal (Other academic)
  • 3.
    Ajalloueian, Fatemeh
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Fransson, Moa
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Tavanai, Hossein
    Massuni, Mohammad
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    LeBlanc, Katarina
    Arpanaei, Ayyoob
    Magnusson, Peetra
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    Investigation of Human Mesenchymal Stromal Cells Cultured on PLGA orPLGA/Chitosan Electrospun Nanofibers2015In: Journal of Bioprocessing & Biotechniques, ISSN 2155-9821, Vol. 5, no 6, article id 230Article in journal (Refereed)
    Abstract [en]

    We compared the viability, proliferation, and differentiation of human Mesenchymal Stromal Cells (MSC)after culture on poly(lactic-co-glycolic acid) (PLGA) and PLGA/chitosan (PLGA/CH) hybrid scaffolds. We appliedconventional and emulsion electrospinning techniques, respectively, for the fabrication of the PLGA and PLGA/CH scaffolds. Electrospinning under optimum conditions resulted in an average fiber diameter of 166 ± 33 nmfor the PLGA/CH and 680 ± 175 nm for the PLGA scaffold. The difference between the tensile strength of thePLGA and PLGA/CH nanofibers was not significant, but PLGA/CH showed a significantly lower tensile modulusand elongation at break. However, it should be noted that the extensibility of the PLGA/CH was higher than thatof the nanofibrous scaffolds of pure chitosan. As expected, a higher degree of hydrophilicity was seen with PLGA/CH, as compared to PLGA alone. The biocompatibility of the PLGA and PLGA/CH scaffolds was compared usingMTS assay as well as analysis by scanning electron microscopy and confocal microscopy. The results showed thatboth scaffold types supported the viability and proliferation of human MSC, with significantly higher rates on PLGA/CH nanofibers. Nonetheless, an analysis of gene expression of MSC grown on either PLGA or PLGA/CH showed asimilar differentiation pattern towards bone, nerve and adipose tissues.

  • 4.
    Ajalloueian, Fatemeh
    et al.
    Tech Univ Denmark, DTU Food, Nanobio Sci Res Grp, Lyngby, Denmark.
    Lemon, Greg
    Karolinska Inst, Dept Clin Sci Intervent & Technol CLINTEC, Stockholm, Sweden.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Chronakis, Ioannis S.
    Tech Univ Denmark, DTU Food, Nanobio Sci Res Grp, Lyngby, Denmark.
    Fossum, Magdalena
    Karolinska Inst, Dept Womens & Childrens Hlth, Stockholm, Sweden; Karolinska Inst, Ctr Mol Med, CMM 02, Stockholm, Sweden; Karolinska Univ Hosp, Astrid Lindgren Childrens Hosp, Dept Paediat Surg, Sect Urol, Stockholm, Sweden.
    Bladder biomechanics and the use of scaffolds for regenerative medicine in the urinary bladder2018In: Nature reviews. Urology, ISSN 1759-4812, E-ISSN 1759-4820, Vol. 15, no 3, p. 155-174Article, review/survey (Refereed)
    Abstract [en]

    The urinary bladder is a complex organ with the primary functions of storing urine under low and stable pressure and micturition. Many clinical conditions can cause poor bladder compliance, reduced capacity, and incontinence, requiring bladder augmentation or use of regenerative techniques and scaffolds. To replicate an organ that is under frequent mechanical loading and unloading, special attention towards fulfilling its biomechanical requirements is necessary. Several biological and synthetic scaffolds are available, with various characteristics that qualify them for use in bladder regeneration in vitro and in vivo, including in the treatment of clinical conditions. The biomechanical properties of the native bladder can be investigated using a range of mechanical tests for standardized assessments, as well as mathematical and computational bladder biomechanics. Despite a large body of research into tissue engineering of the bladder wall, some features of the native bladder and the scaffolds used to mimic it need further elucidation. Collection of comparable reference data from different animal models would be a helpful tool for researchers and will enable comparison of different scaffolds in order to optimize characteristics before entering preclinical and clinical trials.

  • 5.
    Ajalloueian, Fatemeh
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Tavanai, Hossein
    Hilborn, Jons
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Donzel-Gargand, Olivier
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Leifer, Klaus
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Wickham, Abeni
    Arpanaei, Ayyoob
    Emulsion Electrospinning as an Approach to Fabricate PLGA/Chitosan Nanofibers for Biomedical Applications2014In: BioMed Research International, ISSN 2314-6133, Vol. 2014, p. 475280-Article in journal (Refereed)
    Abstract [en]

    Novel nanofibers from blends of polylactic-co-glycolic acid (PLGA) and chitosan have been produced through an emulsion electrospinning process. The spinning solution employed polyvinyl alcohol (PVA) as the emulsifier. PVA was extracted from the electrospun nanofibers, resulting in a final scaffold consisting of a blend of PLGA and chitosan. The fraction of chitosan in the final electrospun mat was adjusted from 0 to 33%. Analyses by scanning and transmission electron microscopy show uniform nanofibers with homogenous distribution of PLGA and chitosan in their cross section. Infrared spectroscopy verifies that electrospun mats contain both PLGA and chitosan. Moreover, contact angle measurements show that the electrospun PLGA/chitosanmats are more hydrophilic than electrospun mats of pure PLGA. Tensile strengths of 4.94 MPa and 4.21 MPa for PLGA/chitosan in dry and wet conditions, respectively, illustrate that the polyblend mats of PLGA/chitosan are strong enough for many biomedical applications. Cell culture studies suggest that PLGA/chitosan nanofibers promote fibroblast attachment and proliferation compared to PLGA membranes. It can be assumed that the nanofibrous composite scaffold of PLGA/chitosan could be potentially used for skin tissue reconstruction.

  • 6.
    Ajalloueian, Fatemeh
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Zeiai, S.
    Fossum, M.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    A bedside collagen-PLGA nanofibrous construct for autologous transplantation of minced bladder mucosal2012In: Journal of Tissue Engineering and Regenerative Medicine, ISSN 1932-6254, Vol. 6, no suppl 1, p. 128-128Article in journal (Other academic)
    Abstract [en]

    Introduction: Bladder regeneration using minced bladder mucosa is an alternative to costly and time-consuming conventional in vitro culturing of urothelial cells. In this method, the uroepithelium expands in vivo and the patient body appears as an incubator. With our preliminary successes, designing an appropriate scaffold that supports in vivo cell expansion and surgical handling in a clinical setting was our aim. This study, investigates cell expansion in a hybrid construct of collagen/poly (lactic-co-glycolide)(PLGA).

    Materials and methods: An electrospun PLGA mat was placed on a semi-gel collagen inside a mold and covered with a second collagen layer. After gel formation, minced particles of pig bladder mucosa were seeded on the hybrid construct and then processed by plastic compression (PC). The scaffolds were incubated for 2, 4 and 6 weeks in vitro for further studies.

    Results: Tensile tests show an increase in tensile strength of 0.6 ± 0.1 MPa in PC collagen to 3.6 ± 1.1 MPa in hybrid construct. Morphological studies, histological staining and SEM show that the construct has kept its integrity during the time and proliferated urothelial cells have reached confluence after 4 weeks and a multi-layered urothelium after 6 weeks.

    Conclusion: We have designed a mechanically robust scaffold that permits surgical handling and tissue expansion in vivo. The construct is easy-to-use for clinical application in an ordinary surgical operating theater for bladder regeneration.

  • 7.
    Ajalloueian, Fatemeh
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Zeiai, Said
    Fossum, Magdalena
    Hilborn, Jöns G.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Constructs of electrospun PLGA, compressed collagen and minced urothelium for minimally manipulated autologous bladder tissue expansion2014In: Biomaterials, ISSN 0142-9612, E-ISSN 1878-5905, Vol. 35, no 22, p. 5741-5748Article in journal (Refereed)
    Abstract [en]

    Bladder regeneration based on minced bladder mucosa in vivo expansion is an alternative to in vitro culturing of urothelial cells. Here, we present the design of a hybrid, electrospun poly(lactic-co-glycolide) (PLGA) - plastically compressed (PC) collagen scaffold that could allow in vivo bladder mucosa expansion. Optimisation of electrospinning was performed in order to obtain increased pore sizes and porosity to consolidate the construct and to support neovascularisation and tissue ingrowth. Tensile tests showed an increase in average tensile strength from 0.6 MPa for PC collagen to 3.57 MPa for the hybrid construct. The optimised PLGA support scaffold was placed between two collagen gels, and the minced tissue was distributed either on top or both on top and inside the construct prior to PC; this was then cultured for up to four weeks. Morphology, histology and SEM demonstrated that the construct maintained its integrity throughout cell culture. Cells from minced tissue migrated, expanded and re-organised to a confluent cell layer on the top of the construct after two weeks and formed a multilayered urothelium after four weeks. Cell morphology and phenotype was typical for urothelial mucosa during tissue culture. (C) 2014 Elsevier Ltd. All rights reserved.

  • 8.
    Ajalloueian, Fatemeh
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Zeiai, Said
    Rojas, Ramiro
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Fossum, Magdalena
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    One-Stage Tissue Engineering of Bladder Wall Patches for an Easy-To-Use Approach at the Surgical Table2013In: Tissue Engineering. Part C, Methods, ISSN 1937-3384, E-ISSN 1937-3392, Vol. 19, no 9, p. 688-696Article in journal (Refereed)
    Abstract [en]

    We present a method for producing a cell-scaffold hybrid construct at the bedside. The construct is composed of plastic-compressed collagen together with a poly(e-caprolactone) (PCL)-knitted mesh that yields an integrated, natural-synthetic scaffold. This construct was evaluated by seeding of minced bladder mucosa, followed by proliferation in vitro. High mechanical strength in combination with a biological environment suitable for tissue growth was achieved through the creation of a hybrid construct that showed an increased tensile strength (17.9 +/- 2.6 MPa) when compared to plastic-compressed collagen (0.6 +/- 0.12 MPa). Intimate contact between the collagen and the PCL fabric was required to ensure integrity without delamination of the construct. This contact was achieved by surface alkaline hydrolysis of the PCL, followed by adsorption of poly(vinyl) alcohol. The improvement in hydrophilicity of the PCL-knitted mesh was confirmed through water contact angle measurements, and penetration of the collagen into the mesh was evaluated by scanning electron microscopy (SEM). Particles of minced bladder mucosa tissue were seeded onto this scaffold, and the proliferation was followed for 6 weeks in vitro. Results obtained from phase contrast microscopy, SEM, and histological staining indicated that cells migrated from the minced tissue particles and reorganized on the scaffold. Cells were viable and proliferative, with morphological features characteristic of urothelial cells. Proliferation reached the point at which a multilayer with a resemblance to stratified urothelium was achieved. This successful method could potentially be used for in vivo applications in reconstructive urology as an engineered autologous tissue transplant without the requirement for in vitro culture before transplantation.

  • 9. Ananta, M.
    et al.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Aibibu, D.
    Brown, R. A.
    Mudera, V.
    A Novel Poly(L-Lactide-co-e-Caprolactone)-Collagen Hybrid Construct for Application in Tissue Engineering2007In: Termis-EU Meeting Abstracts, London, UK September 4-7 2007: [Published in Tissue Engineering, vol. 13, nr. 7], Mary Ann Liebert Inc. , 2007, p. 1637-1637Conference paper (Other academic)
    Abstract [en]

    A biodegradable hybrid construct consisting of a slow degrading poly(L-lactide-co-e-caprolactone) (PLA-e-CL) knitted mesh, plastically compressed (1) between two collagen gels was fabricated and tested in vitro for tissue engineering applications. The polymer mesh was incorporated to give greater mechanical stability to the compressed collagen scaffolds.

    The hybrid construct was characterized for fluid (weight) loss and cell viability during compression and mechanical properties.

    Hybrid constructs embedded and surface layered with human dermal

    fibroblasts (2, Eþ5 per 5 ml) were cultured for up to one week

    in static culture. Quantitative and qualitative data on cell viability

    and proliferation were obtained.

    It was found that the fluid (weight) loss in plastic compression

    of the hybrid construct was time dependent and not weight dependent

    at an applied load of 240 grams. No significant cell death

    was observed during the plastic compression process and a homogenous

    cell distribution was achieved. One week of static culture

    showed that the cultivated hybrid construct retained its

    mechanical properties with no evidence of degradation, and cells

    inside the constructs as well as layered on top of the constructs

    proliferated.

    We found the PLA-e-CL-Collagen hybrid construct a useful

    three-dimensional scaffold for tissue engineering of stratified tissues

    and potential applications in bladder wall, blood vessels and

    skin are currently being explored.

  • 10. Arnander, Claes
    et al.
    Westermark, Anders
    Veltheim, Riikka
    Docherty-Skogh, Ann-Charlotte
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Engstrand, Thomas
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Three-Dimensional Technology and Bone Morphogenetic Protein in Frontal Bone Reconstruction2006In: Journal of Craniofacial Surgery, Vol. 17, no 2, p. 275-279Article in journal (Refereed)
    Abstract [en]

    Osteoinductive bone morphogenetic proteins (BMPs) may be used in humans to facilitate healing of bony defects. The effect of different BMPs is, as with many other growth factors, highly dependent on the delivery vehicle. Bovine type I collagen is currently used in the clinical setting as a carrier and has been approved in several countries for human use. Here, we report the reconstruction of a frontal bone defect using heparin together with bovine type I collagen, hyaluronic acid, and fibrin as vehicles for BMP-2. A bony structure was created on the back of the patient by treating the latissimus dorsi muscle with the growth factor. A polyamide mold was used as a template to achieve the desired shape. The bone structure was transplanted into the defect site via microsurgical techniques. Although the prefabricated bone was not large enough tocover the entire frontal defect, the reconstruction was completed by using an additional cranial implant.

  • 11.
    Asplund, Basse
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Bowden, Tim
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Mathisen, Torbjörn
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Variable Hard Segment Length in Poly(urethane urea) through Excess of Diisocyanate and Vapor Phase Addition of Water2006In: Macromolecules, Vol. 39, p. 4380-4385Article in journal (Refereed)
    Abstract [en]

    Poly(urethane urea)s with hard segments derived only from diisocyanate linked via urea linkages were synthesized using a new and simple one-pot method. The creation of urea linkages were done via creating the amine in situ by adding water in vapor phase slowly and continuously. This synthesis method eliminates the tedious control to approach stoichiometry, is less sensitive to impurities, involves no intermediate isolation steps, and does not involve any chain extender. A study using a two-armed poly(-caprolactone) as soft segment and methyl 2,6-diisocyantohexanoate (LDI) as the hard segment was performed. The length of the hard segment was varied from 4.8 to 11.6 LDI units. Stress-strain measurements showed an increase in elastic modulus, 146 to 235 MPa, when increasing the hard segment length, while the elongation at break decreased, 980 to 548%. IR spectroscopy showed an increase in hydrogen bonding when increasing the hard segment length. The synthesis was also shown to be applicable to common diisocyanates such as HDI, TDI, and MDI.

  • 12.
    Asplund, Basse
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Sperens, Jenny
    Mathisen, Torbjorn
    Hilborn, Jons
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Effects of hydrolysis on a new biodegradable co-polymer2006In: Journal of Biomaterials Science. Polymer Edition, ISSN 0920-5063, E-ISSN 1568-5624, Vol. 17, no 6, p. 615-630Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to examine the feasibility of using a new low-modulus biodegradable thermoplastic elastomer for in vivo application as a stent cover. The new polymer, a thermoplastic elastomer, consists of a three-armed co-polymer of poly(lactide)acid (PLLA), poly(trimethylene carbonate) (PTMC) and poly(caprolactone) (PCL). A degradation study was performed in a buffer solution at 37 degrees C for 4 and 6 weeks. The effect of degradation on mechanical properties was studied by stress-strain measurements and explained by using modulated DSC, GPC and mass measurements. A tapered block of PLLA and trimethylene carbonate connecting the crystalline outer part and the inner elastic part was highly susceptible to hydrolysis and caused rapid degradation and subsequent loss of mechanical properties. Random chain scission and homogenous hydrolysis resulted in a loss in mass and molecular weight. After 6 weeks of in vitro hydrolysis the molecular weight had decreased 54% and the elongation-at-break dropped from more than 300% to 90%. A medium free cell seeding study showed that endothelial cells adhered well to the polymeric material. An indicative animal study with the polymer acting as a stent cover showed very low levels of inflammation however, pronounced neointima thickening was observed which was probably due to the premature failure of the material.

  • 13.
    Asplund, Basse
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Sperens, Jenny
    Mathisen, Torbjörn
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Effects of hydrolysis on a new biodegradable co-polymer2006In: Journal of Biomaterials Science, Polymer Edition, Vol. 17, no 6, p. 615-630Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to examine the feasibility of using a new low-modulus biodegradable thermoplastic elastomer for in vivo application as a stent cover. The new polymer, a thermoplastic elastomer, consists of a three-armed co-polymer of poly(lactide)acid (PLLA), poly(trimethylene carbonate) (PTMC) and poly(caprolactone) (PCL). A degradation study was performed in a buffer solution at 37°C for 4 and 6 weeks. The effect of degradation on mechanical properties was studied by stress-strain measurements and explained by using modulated DSC, GPC and mass measurements. A tapered block of PLLA and trimethylene carbonate connecting the crystalline outer part and the inner elastic part was highly susceptible to hydrolysis and caused rapid degradation and subsequent loss of mechanical properties. Random chain scission and homogenous hydrolysis resulted in a loss in mass and molecular weight. After 6 weeks of in vitro hydrolysis the molecular weight had decreased 54% and the elongation-at-break dropped from more than 300% to 90%. A medium free cell seeding study showed that endothelial cells adhered well to the polymeric material. An indicative animal study with the polymer acting as a stent cover showed very low levels of inflammation; however, pronounced neointima thickening was observed which was probably due to the premature failure of the material.

  • 14.
    Atthoff, Björn
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Danielsson, C
    Frey, P
    Gupta, B
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Scaffolds combining compliance and strength2002In: International Journal of Artificial Organs, Vol. 25, no 7, p. 640-641Article in journal (Refereed)
  • 15.
    Atthoff, Björn
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Bowden, Tim
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Novel metal free catalyst for bulk polymerization of lactides, using a cationic ring opening polymerization procedure2003In: PMSE Preprints (2003), 88, 2003, p. 369-Conference paper (Refereed)
  • 16.
    Atthoff, Björn
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Nederberg, Fredrik
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Bowden, Tim
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Sulfate end functionalized heparin mimetic biodegradable poly(trimethylenecarbonate)2005In: Polymer Preprints (American Chemical Society, Division of Polymer Chemistry) 46(1) 2005, 2005, p. 473-474Conference paper (Refereed)
  • 17.
    Atthoff, Björn
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Nederberg, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Söderberg, Lennart
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Surface Biotechnology.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Synthetic Biodegradable Ionomers that Engulf, Store, and Deliver Intact Proteins2006In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 7, no 8, p. 2401-2406Article in journal (Refereed)
    Abstract [en]

    Telechelic anionic and cationic biodegradable ionomers capable of loading, storing, and releasing proteins are presented. Two different ionomers have been synthesized with either anionic or cationic end groups. The reaction was done quantitatively as shown by 1H NMR. The swelling properties of the hydrophobic poly(trimethylene carbonate) polymer are contributed to the ionic end groups that display hydrophilic properties. Depending on the molecular weight of the ionomer, and also on the ionic charge, the materials swell differently in water, from ~50% for Mw = 12 000 g/mol to ~500% when dealing with 2000 g/mol. The high swelling led us to believe that it would be possible to load and release proteins preferably in a still active form. As models, two different proteins were chosen: hemoglobin and cytochrome c. The swelling and release study shows that both ionomers possess the capability to adsorb and later release the proteins with retained structure. Release measurements from both the swollen and dried states have been evaluated with similar results, showing that the dried state seems to release a little bit less than the swollen one. These kinds of materials should be interesting for a wide variety of applications where drug and protein release is wanted, as well as in applications such as protein separation media.

  • 18.
    Aulin, C.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Jensen-Waern, M.
    Ekman, S.
    Hagglund, M.
    Engstrand, T.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Hedenqvist, P.
    Cartilage repair of experimentally 11 induced osteochondral defects in New Zealand White rabbits2013In: Laboratory Animals. Journal of the Laboratory Animal Science Association, ISSN 0023-6772, E-ISSN 1758-1117, Vol. 47, no 1, p. 58-65Article in journal (Refereed)
    Abstract [en]

    Articular cartilage has a limited capacity for self-repair in adult humans, and methods used to stimulate regeneration often result in re-growth of fibrous cartilage, which has lower durability. No current treatment option can provide complete repair. The possibility of growth factor delivery into the joint for cartilage regeneration after injury would be an attractive treatment option. A full thickness osteochondral defect of 4 mm in diameter and 2 mm deep was created by mechanical drilling in the medial femoral condyle in 20 female adult New Zealand White rabbits. In an attempt to improve regeneration a hyaluronic hydrogel system, with or without bone morphogenetic protein-2 (BMP-2) was delivered intraarticularly. The contralateral joint defect was treated with saline as control. Throughout the study, rabbits were clinically examined and after 12 (n = 6) or 24 (n = 9) weeks, the rabbits were euthanized and the joints evaluated by histology. The defects healed with fibrocartilage like tissue, and the filling of the defects ranged from less than 25% to complete. The healing of the defects varied both inter- and intra-group wise. Treatment with hyaluronan gel with or without BMP-2 had no effect on cartilage regeneration compared with controls. Instead, severe ectopic bone formation was found in seven joints treated with BMP-2. In conclusion, the present study shows that neither treatment with hyaluronic gel alone, nor in combination with BMP-2, improves the healing of an induced cartilage defect in rabbits. It further shows that BMP-2 can induce ectopic bone formation, which severely affects the functionality of the joint.

  • 19.
    Aulin, Cecilia
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Atthoff, Björn
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Andersson, J
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    In vitro/ Produced Extracellular Matrix Scaffolds2005In: European Tissue Engineering Society International Conference, München 8 Aug – 3 sept 2005, oral presentation, 2005Conference paper (Other (popular scientific, debate etc.))
  • 20.
    Aulin, Cecilia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Bergman, Kristoffer
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Jensen-Waern, Marianne
    Hedenqvist, Patricia
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Engstrand, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    In situ cross-linkable hyaluronan hydrogel enhances chondrogenesis2011In: Journal of tissue engineering and regenerative medicine, ISSN 1932-6254, Vol. 5, no 8, p. E188-E196Article in journal (Refereed)
    Abstract [en]

    The present work describes the feasibility of a cross-linkable injectable hyaluronan hydrogel for cartilage repair. The hydrogel used is a two-component system based on aldehyde-modified hyaluronan and hydrazide-modified polyvinyl alcohol, which are rapidly cross-linked in situ upon mixing. The in vitro study showed that chondrocytes and mesenchymal cells cultured in the gel form cartilage-like tissue, rich in glycosaminoglycans, collagen type II and aggrecan. In a rabbit animal model the injection of the hydrogel improved the healing of a full-thickness cartilage defect created in the knee as compared to non-treated controls. This rabbit study showed that the regenerated cartilage defects stained more intensely for type II collagen upon treatment with the hydrogel. The hyaluronan-based hydrogel may be used as a delivery vehicle for both growth factors and/or cells for cartilage repair. The in vivo study also indicated that the hydrogel alone has a beneficial effect on cartilage regeneration.

  • 21.
    Aulin, Cecilia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Forough, F
    Brown, R
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    USING cells as micro factories for ECM polymer hybrid material production2008In: TERMIS EU 2008 Porto Meeting June 22–26, 2008 Porto Congress Center–Alfândega Portugal: [Published in Tissue Engineering. Part A, vol. 14, nr. 5], Mary Ann Liebert Inc. , 2008, Vol. 14, no 5, p. 925-925Conference paper (Other academic)
  • 22.
    Aulin, Cecilia
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Foroughi, F
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Brown, R
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Extracellular matrix based scaffold produced by mechanical stimulation of fibroblasts2007In: Second International Conference on Mechanics of Biomaterials & Tissues, Lihue, Kauai, USA, 9-13 December 2007, poster presentation, 2007Conference paper (Other (popular scientific, debate etc.))
  • 23.
    Aulin, Cecilia
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Foroughi, F
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Cell produced ECM on engineered polymer structures2006In: Tissue Engineering and Regenerative Medicine International Society Conference, Rotterdam, 08 – 11 oktober 2006, oral presentation, 2006Conference paper (Other (popular scientific, debate etc.))
  • 24.
    Aulin, Cecilia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Foroughi, F.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Designing Extracellular Matrix Scaffolds by Dynamic culture of fibroblasts2007In: TERMIS-EU Meeting Abstracts London, UK September 4–7, 2007: [published in Tissue Engineering, vol. 13, nr. 7], Mary Ann Liebert , 2007, Vol. 13, no 7, p. 1667-1667Conference paper (Other academic)
    Abstract [en]

    Our bodies are constantly exposed to different sorts of mechanical forces, from muscle tension to wound healing. Connective tissue adapts its extracellular matrix (ECM) to changes in mechanical load and the influence of mechanical stimulation on fibroblasts has been studied for a long time [1, 2]. When exposed to forces, fibroblasts are known to respond with expression and remodeling of ECM proteins, in particular collagen type I [3]. In this study the effect of dynamic culture conditions on human dermal fibroblasts was evaluated in terms of deposition and remodeling of ECM, with the aim of producing an ECM based scaffold. The fibroblasts were grown on compliant polymer supports either in a bioreactor with a pulsating flow or under static conditions. By applying dynamic culture conditions, the collagen deposition on the polymer supports increased fivefold. Scanning electron microscopy showed that polymer fibers were well integrated with cells and ECM and alignment along the polymer fibers was observed. Scaffold design should aim at creating structures that can help guiding the cells to form new, functional tissue. The presented system may present a new way of producing designed extracellular matrix based scaffolds for tissue engineering.

  • 25. Backly, R. E.
    et al.
    Todeschi, M. R.
    Varghese, Oommen
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Cancedda, R.
    Mastrogiacomo, M.
    Host cell recruitment patterns by BMP-2 releasing hyaluronic acid gels in a mouse subcutaneous model2014In: Journal of Tissue Engineering and Regenerative Medicine, ISSN 1932-6254, E-ISSN 1932-7005, Vol. 8, p. 65-65Article in journal (Other academic)
  • 26.
    Bergman, Kristoffer
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Bowden, Tim
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Hyaluronic acid cross-linking chemistry2005In: 8th International Symposium of Polymers for Advanced Technologies, 13th-16th Sept. 2005, Budapest, Hungary, 2005Conference paper (Other scientific)
  • 27.
    Bergman, Kristoffer
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry.
    Elvingson, Christer
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry.
    Svensk, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry.
    Hyaluronic acid derivatives prepared in aqueous media by triazine-activated amidation2007In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 8, no 7, p. 2190-2195Article in journal (Refereed)
    Abstract [en]

    A method is presented for the preparation of hyaluronic acid derivatives obtained through triazine-activated amidation. A number of amines were successfully reacted with hyaluronic acid carboxyl groups using 2-chloro-4,6-dimethoxy-1,3,5-triazine as an activating species in a mixture of water and acetonitrile under neutral conditions. By varying the amount of triazine reagent, it was possible to control the degree of modification. Depending on the amine chosen, degrees of modification ranging from 3 to 20% were obtained when using 0.5 equiv of the triazine to hyaluronic acid carboxyl groups. The possibility to perform the reaction in a mixture of water and acetonitrile facilitates the introduction of a wide range of both hydrophilic and hydrophobic amines. Triazine-activated amidation appears to be a highly versatile, controllable, and relatively mild technique for modification of hyaluronic acid, and we predict that it will be useful in the design of novel hyaluronic acid based biomaterials.

  • 28.
    Bergman, Kristoffer
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Mild modifications of hyaluronan for fine-tuning of mechanical and chemical properties2003In: Europolymer Congress, 2003, Stockholm, Sweden, 2003Conference paper (Other academic)
  • 29.
    Bergman, Kristoffer
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Modification of Hyaluronan by Triazine-Promoted Amidation in Aqueous Media2006In: 232nd ACS National Meeting, 10th-14th Sept. 2006, San Francisco, California, USA, 2006Conference paper (Other (popular science, discussion, etc.))
  • 30.
    Bergman, Kristoffer
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Preparation and evaluation of an injectable hyaluronan hydrogel for therapeutic applications2007In: 7th International conference on Hyaluronan, 22nd-27th April 2007, Charleston, South Carolina, USA, 2007Conference paper (Other (popular science, discussion, etc.))
  • 31.
    Bermejo, Daniel
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Kadekar, Sandeep
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Tavares da Costa, Marcus Vinicius
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Podiyan, Oommen
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Gamstedt, E. Kristofer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Mechanics.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Varghese, Oommen P.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    First Aldol-Crosslinked Hyaluronic Acid Hydrogel: Fast and Hydrolytically Stable Gel with Tissue Adhesive PropertiesIn: Chemical Sciences Journal, ISSN 2150-3494Article in journal (Refereed)
    Abstract [en]

    Currently, there are limited approaches to tailor 3D scaffolds crosslinked with a stable covalent C-C bond that does not require any catalysts or initiators. We present here the first hydrogels employing aldol condensation chemistry that exhibit exceptional physicochemical properties. We investigated the aldol-crosslinking chemistry using two types of aldehyde-modified hyaluronic acid (HA) derivatives, namely; an enolizable HA-aldehyde (HA-Eal) and a non-enolizable HA-aldehyde (HA-Nal). Hydrogels formed using HA-Eal demonstrate inferior crosslinking efficiency (due to intramolecular loop formation), when compared with hydrogels formed by mixing HA-Eal and HA-NaI leading to a cross-aldol product. The change in mechanical properties as a result of crosslinking at different pH is determined using rheological measurements and is interpreted in terms of molecular weight between cross-links (Mc). The novel HA cross-aldol hydrogels demonstrate excellent hydrolytic stability and favorable mechanical properties but allow hyaluronidase mediated enzymatic degradation. Interestingly, residual aldehyde functionality within the aldol product leads to adhesion to tissue as demonstrated by bonding two bone tissues. The aldehyde functionality also permits facile post-synthetic modifications with nucleophilic reagents such as Alexa FluorTM 488. Finally, we demonstrate that the novel hydrogel is biocompatible with encapsulated stem cells that show a linear rate of expansion in our 3–6 days of study.

  • 32.
    Bermejo-Velasco, Daniel
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Azémar, Alice
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Oommen, Oommen P.
    Bioengineering and Nanomedicine Lab, Faculty of Medicine and Health Technologies and BioMediTech Institute, Tampere University, Korkeakoulunkatu 3, Tampere 33720, Finland.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Varghese, Oommen P.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Modulating thiol pKa promotes disulfide formation at physiological pH: An elegant strategy to design disulfide cross-linked hyaluronic acid hydrogels2019In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, no 3, p. 1412-1420Article in journal (Refereed)
    Abstract [en]

    The disulfide bond plays a crucial role in protein biology and has been exploited by scientists to develop antibody-drug conjugates, sensors and for the immobilization other biomolecules to materials surfaces. In spite of its versatile use, the disulfide chemistry suffers from some inevitable limitations such as the need for basic conditions (pH > 8.5), strong oxidants and long reaction times. We demonstrate here that thiol-substrates containing electron-withdrawing groups at the β-position influence the deprotonation of the thiol group, which is the key reaction intermediate in the formation of disulfide bonds. Evaluation of reaction kinetics using small molecule substrate such as L-cysteine indicated disulfide formation at a 2.8-fold higher (k1 = 5.04 x 10-4 min-1) reaction rate as compared to the conventional thiol substrate, namely 3-mercaptopropionic acid (k1 = 1.80 x 10-4 min-1) at physiological pH (pH 7.4). Interestingly, the same effect could not be observed when N-acetyl-L-cysteine substrate (k1 = 0.51 x 10-4 min-1) was used. We further grafted such thiol-containing molecules (cysteine, N-acetyl-cysteine, and 3-mercaptopropionic acid) to a biopolymer namely hyaluronic acid (HA) and determined the pKa value of different thiol groups by spectrophotometric analysis. The electron-withdrawing group at the β-position reduced the pKa of the thiol group to 7.0 for HA-cysteine (HA-Cys); 7.4 for N-acetyl cysteine (HA-ActCys) and 8.1 for HA-thiol (HA-SH) derivatives respectively. These experiments further confirmed that the concentration of thiolate (R-S-) ions could be increased with the presence of electron-withdrawing groups, which could facilitate disulfide cross-linked hydrogel formation at physiological pH. Indeed, HA grafted with cysteine or N-acetyl groups formed hydrogels within 3.5 minutes or 10 hours, respectively at pH 7.4. After completion of crosslinking reaction both gels demonstrated a storage modulus G’ ≈3300–3500 Pa, indicating comparable levels of crosslinking. The HA-SH gel, on the other hand, did not form any gel at pH 7.4 even after 24 h. Finally, we demonstrated that the newly prepared hydrogels exhibited excellent hydrolytic stability but can be degraded by cell-directed processes (enzymatic and reductive degradation). We believe our study provides a valuable insight on the factors governing the disulfide formation and our results are useful to develop strategies that would facilitate generation of stable thiol functionalized biomolecules or promote fast thiol oxidation according to the biomedical needs.

  • 33.
    Bermejo-Velasco, Daniel
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Nawale, Ganesh N.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Oommen, Oommen P.
    Bioengineering and Nanomedicine Lab, Faculty of Biomedical Sciences and Engineering, Tampere University of Technology, and BioMediTech Institute, 33720, Tampere, Finland.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Varghese, Oommen P.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Thiazolidine chemistry revisited: a fast, efficient and stable click-type reaction at physiological pH2018In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 54, no 88, p. 12507-12510Article in journal (Refereed)
    Abstract [en]

    We describe the fast reaction kinetics between 1,2-aminothiols and aldehydes. Under physiological conditions such a click-type reaction afforded a thiazolidine product that remains stable and did not require any catalyst. This type of bioorthogonal reaction offers enormous potential for the coupling of biomolecules in an efficient and biocompatible manner.

  • 34.
    Berts, Ida
    et al.
    Uppsala University, Science for Life Laboratory, SciLifeLab. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Fragneto, Giovanna
    Institut Laue-Langevin.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Rennie, Adrian R.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Physics.
    Tuning the density profile of surface-grafted hyaluronan and the effect of counter-ions2013In: European Physical Journal E, ISSN 1292-8941, Vol. 36, no 7, p. 70-Article in journal (Refereed)
    Abstract [en]

    The present paper investigates the structure and composition of grafted sodium hyaluronanat a solid-liquid interface using neutron reflection. The solvated polymer at the surface could be described with a density profile that decays exponentially towards the bulk solution. The density profileof the polymer varied depending on the deposition protocol. A single-stage deposition resulted in denser polymer layers, while layers created with a two-stage deposition process were more diffuse and had an overall lower density. Despite the diffuse density profile, two-stage deposition leads to a highersurface excess. Addition of calcium ions causes a strong collapse of the sodium hyaluronan chains, increasing the polymer density near the surface. This effect is more pronounced on the sample prepared by two-stage deposition due to the initial less dense profile. This study provides an understanding at a molecular level of how surface functionalization alters the structure and howsurface layers respond to changes in calcium ions in the solvent.

  • 35.
    Berts, Ida
    et al.
    Uppsala University, Science for Life Laboratory, SciLifeLab. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Gerelli, Yuri
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Rennie, Adrian R.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Physics.
    Structure of polymer and particle aggregates in hydrogel composites2013In: Journal of Polymer Science Part B: Polymer Physics, ISSN 0887-6266, E-ISSN 1099-0488, Vol. 51, no 6, p. 421-429Article in journal (Refereed)
    Abstract [en]

    Knowledge of the structure of a biomaterial is usually vital to control its function. This article provides a structural characterization of a hyaluronan scaffold that has demonstrated good biocompatibility and is used to induce bone regeneration. Hyaluronan hydrogels are appealing materials that can function as a matrix to incorporate both organic and inorganic substances to enhance tissue growth. Because of the intrinsic properties of this swollen matrix, one needs a very sensitive technique that can be applied in situ to determine the organization of the polymers in a gel. Small-angle neutron scattering is used to determine the characteristics of the inhomogeneous structure of the hydrogel both with and without added particles. The results are interpreted using models of structure with two length scales that are beyond the traditional picture of homogeneous gels. The observed structure and the dimensions can explain the previously reported rheological properties of gels containing different amount of polymers. Hydroxyapatite nanoparticles added to the gel are frozen in the gel matrix. We are able to determine the distribution and shape of these particles as they aggregate around the polymer chains. We have also concluded, in this case, that the particle structure is concentration independent. Information about the nanostructure for an applicable biomaterial guides the formulation, preparation, and use that should lead to further understanding of its exploitation.

  • 36.
    Billström, Gry Hulsart
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Orthopaedics.
    Piskounova, Sonya
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Gedda, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Biomedical Radiation Sciences.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Larsson, Sune
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Orthopaedics.
    Improved bone formation by altering surface area of hyaluronan-based hydrogel carrier for bone morphogenetic protein-22012In: Bone, ISSN 8756-3282, E-ISSN 1873-2763, Vol. 50, p. S114-S114Article in journal (Other academic)
  • 37. Bisson, I
    et al.
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Wurm, F
    Meyrat, B
    Frey, P
    Human urothelial cells grown on collagen adsorbed to surface-modified polymers2002In: Urology, Vol. 60, no 1, p. 176-180Article in journal (Refereed)
  • 38. Bisson, I
    et al.
    Kosinski, M
    Ruault, S
    Gupta, B
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Wurm, F
    Frey, P
    Acrylic acid grafting and collagen immoblization on poly (ethylene terephthalate) surfaces for adherence and growth of human bladder smooth muscle cells2002In: Biomaterials, Vol. 23, no 15, p. 3149-3158Article in journal (Refereed)
  • 39. Bjursten, LM
    et al.
    Rosengren, A
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Surface Biotechnology. Department of Materials Chemistry, Polymer Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical and Analytical Chemistry.
    Marcolongo, M
    Johansson, JA
    Hilborn, Jöns
    Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Foreign body reaction is elicited by mechanical properties of implanted materials2003In: Faseb Journal, Vol. 17, no 5, p. A1197-Article in journal (Refereed)
  • 40.
    Bowden, Tim
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Eriksson, Niklas
    A metal-free catalyst for the catalytic cationic ring opening polymerization of lactones2003In: PMSE Preprints (2003), 88, 2003, p. 535-536Conference paper (Refereed)
  • 41.
    Brännvall, Karin
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Bergman, Kristoffer
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry.
    Wallenquist, Ulrika
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Svahn, Stefan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry.
    Forsberg-Nilsson, Karin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Enhanced neuronal differentiation in a three-dimensional collagen-hyaluronan matrix2007In: Journal of Neuroscience Research, ISSN 0360-4012, E-ISSN 1097-4547, Vol. 85, no 10, p. 2138-2146Article in journal (Refereed)
    Abstract [en]

    Efficient 3D cell systems for neuronal induction are needed for future use in tissue regeneration. In this study, we have characterized the ability of neural stem/progenitor cells (NS/PC) to survive, proliferate, and differentiate in a collagen type I-hyaluronan scaffold. Embryonic, postnatal, and adult NS/PC were seeded in the present 3D scaffold and cultured in medium containing epidermal growth factor and fibroblast growth factor-2, a condition that stimulates NS/PC proliferation. Progenitor cells from the embryonic brain had the highest proliferation rate, and adult cells the lowest, indicating a difference in mitogenic responsiveness. NS/PC from postnatal stages down-regulated nestin expression more rapidly than both embryonic and adult NS/PC, indicating a faster differentiation process. After 6 days of differentiation in the 3D scaffold, NS/PC from the postnatal brain had generated up to 70% neurons, compared with 14% in 2D. NS/PC from other ages gave rise to approximately the same proportion of neurons in 3D as in 2D (9-26% depending on the source for NS/PC). In the postnatal NS/PC cultures, the majority of III-tubulin-positive cells expressed glutamate, -aminobutyric acid, and synapsin I after 11 days of differentiation, indicating differentiation to mature neurons. Here we report that postnatal NS/PC survive, proliferate, and efficiently form synapsin I-positive neurons in a biocompatible hydrogel.

  • 42.
    Cantoni, Federico
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Johansson, Sofia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Pohlit, Hannah
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Porras, Ana Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Samanta, Ayan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Tenje, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    2D and 3D patterning of biological hydrogels for organ-on-chip applications2018Conference paper (Other academic)
  • 43. Carrot, G
    et al.
    Rutot-Houze, D
    Pottier, A
    Degee, P
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Dubois, P
    Surface-initiated ring-opening polymerization: A versatile method for nanoparticle ordering.2002In: Macromolecules, Vol. 33, no 22, p. 8400-8404Article in journal (Refereed)
  • 44.
    Della Martina, A
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Garamszegi, L
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Pore size modification of macroporous crosslinked poly (dicyclopentadiene)2003In: Journal of Polymer Science Part A-Polymer Chemistry, Vol. 41, p. 2036-2046Article in journal (Refereed)
  • 45. Della Martina, A
    et al.
    Garamszegi, L
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Surface functionalization of cross-linked poly(dicyclopentadiene)2003In: Reactive & Functional Polymers, Vol. 57, no 1, p. 49-55Article in journal (Refereed)
  • 46.
    Della Martina, A
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Gradient porosity poly (dicyclopentadiene)2001In: Journal of Materials Research, Vol. 16, no 7, p. 2045-2052Article in journal (Refereed)
  • 47. Docherty-Skogh, Ann-Charlott
    et al.
    Bergman, Kristoffer
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Waern, Marianne Jensen
    Ekman, Stina
    Hultenby, Kjell
    Ossipov, Dimitri
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Engstrand, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Bone morphogenetic protein-2 delivered by hyaluronan-based hydrogel induces massive bone formation and healing of cranial defects in minipigs2010In: Plastic and reconstructive surgery (1963), ISSN 0032-1052, E-ISSN 1529-4242, Vol. 125, no 5, p. 1383-1392Article in journal (Refereed)
    Abstract [en]

    Background: Reconstruction of large craniofacial bone defects is a challenge using bone transplants or alloplastic materials. The use of bone morphogenetic protein (BMP)-2 together with a suitable carrier is an attractive option that may facilitate new bone formation. The authors have developed a hydrogel that is formed in situ by the cross-linking of multifunctional hyaluronic acid and polyvinyl alcohol derivatives mixed with hydroxyapatite nanoparticles, in the presence of BMP-2. The aim of this study was to evaluate the suitability of the hydrogel as a carrier for BMP-2 in repairing critical size cranial defects in a minipig model. Methods: Cranial defects (2 × 4 cm) were created in 14 minipigs. The experimental groups were as follows: group 1, craniotomy and application of 5 ml of hydrogel with 1.25 mg of BMP-2 (n = 6); group 2, craniotomy and application of 5 ml of hydrogel without BMP-2 (n = 6); and group 3, craniotomy with no further treatment (n = 2). Results: After 3 months, computed tomographic and histologic examinations were performed. There was spontaneous ossification in the untreated group, but the healing was incomplete. The hydrogel alone demonstrated no further effects. The addition of 1.25 mg of BMP-2 to the hydrogel induced a greater than 100 percent increase in bone volume (p = 0.003) and complete healing of the defects. Histologic examination revealed compact lamellar bone in the BMP group without intertrabecular fibrous tissue, as was seen in the other groups. The hydrogel was resorbed completely within 3 months and, importantly, caused no inflammatory reaction. Conclusion: The injectable hydrogel may be favorable as a BMP-2 carrier for bone reconstruction.

  • 48. Dudeck, O.
    et al.
    Jordan, O.
    Hoffmann, K. T.
    Okuducu, A. F.
    Husmann, I.
    Kreuzer-Nagy, T.
    Tesmer, K.
    Podrabsky, P.
    Bruhn, H.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Rüfenacht, D. A.
    Doelker, E.
    Felix, R.
    Embolization of experimental wide-necked aneurysms with iodine-containing polyvinyl alcohol solubilized in a low-angiotoxicity solvent2006In: American Journal of Neuroradiology, ISSN 0195-6108, E-ISSN 1936-959X, Vol. 27, no 9, p. 1849-1855Article in journal (Refereed)
    Abstract [en]

    BACKGROUND AND PURPOSE: To evaluate the ready-to-use iodine-containing polyvinyl alcohol (I-PVA) dissolved in the low angiotoxic solvent N-methyl pyrrolidone (NMP) for embolization of porcine wide-necked aneurysms.

    METHODS: Fourteen broad-based carotid sidewall aneurysms were surgically constructed in 7 swine. I-PVA (40%) in NMP was injected under temporary balloon occlusion bridging the aneurysm neck. After 4 weeks, follow-up angiography, multisection CT angiography (MSCTA), and 3T MR imaging including MR angiography (MRA) sequences were performed. Afterward, harvested aneurysms were investigated histopathologically.

    RESULTS: The liquid embolic was well visible under fluoroscopy and displayed a favorable precipitation pattern, allowing for controlled polymer delivery. Ten aneurysms (71%) were initially completely occluded, whereas in 1 aneurysm, a minimal polymer leakage was observed. The other 4 aneurysms (29%) were almost completely occluded. One animal suffered a lethal rebleeding from the anastomosis after uneventful embolization. Aneurysms embolized with I-PVA could be discriminated well from the parent artery without beam-hardening artifacts on MSCTA, and no susceptibility artifacts were encountered on MR imaging. Histologic examination revealed all aneurysms covered with a membrane of fibroblasts and an endothelial cell layer while a moderate intraaneurysmal inflammatory response to the polymer was observed.

    CONCLUSION: I-PVA dissolved in NMP has proved its effectiveness for the embolization of experimental wide-necked aneurysms. This precipitating liquid embolic offers several interesting features in that it needs no preparation before use and no radiopaque admixtures, the latter allowing for artifact-free evaluation of treated aneurysms with MSCTA and MRA. Moreover, it uses NMP as a solvent, which has only a low angiotoxicity.

  • 49. Dudeck, Oliver
    et al.
    Jordan, Oliver
    Hoffmann, Karl-Titus
    Tesmer, Kai
    Kreuzer-Nagy, Tibor
    Podrabsky, Petr
    Heise, Michael
    Meyer, Rudolf
    Okuducu, Ali Fuat
    Bruhn, Harald
    Hilborn, Jöns
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Polymer Chemistry. polymerkemi.
    Rüfenacht, Daniel
    Doelker, Eric
    Felix, Roland
    Intrinsically radiopaque iodine-containing polyvinyl alcohol as a liquid embolic agent: evaluation in experimental wide-necked aneurysms2006In: Journal of Neurosurgery, Vol. 104, no 2, p. 290-297Article in journal (Refereed)
  • 50.
    Ekdahl, Kristina N
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    Fromell, Karin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Nilsson, Bo
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical Immunology.
    The innate immunity response: A key factor in biocompatibility2017In: Bioresorbable Polymers for Biomedical Applications: From Fundamentals to Translational Medicine / [ed] Giuseppe Perale & Jöns Hilborn, Elsevier, 2017, p. 85-94Chapter in book (Refereed)
1234 1 - 50 of 188
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